Metal forming lubricants and their use



Patented Feb. 14, 1939 UNITED STATES PATENT OFFI E.

' amasss- Nelson W. Dempsey, Worcester, Mass assignor No Drawing. Application April 8, 1937,

Serial No. 135,820

' 8 Claims.

tended for reworking by 'deep drawing, pressing and stamping in suitable dies.

Heretofore various lubricants, such as oils and greases, have been used to eifect a thin trans-- parent film on wire and rods intended for upsetting purposes, but these lubricants are in themselves so soft as to be wiped off to an extent that jeopardizes the lubricating qualities during subsequent reworking, or permit abrasive particles to adhere to the wire or rods, or have such a low film strength as to break down'under the high pressures in the type of working under con-- sideration. All of these defects lead to poor lubricating qualities and cause undue wear on the forming dies.

The present invention provides a hard-film that neither wipes off nor tends to accumulate adhering abrasive-particles. This film has a lubricating surface of a hardness and strength comparable to that obtained through the use of wire drawing soap, waxes or metallic stearate, but,pos sesses a transparency comparable to grease or oil films and can be removed simply by immersion in water at temperatures above its melting point.

On hot and cold rolled metal strip to be reworked by deep drawing, pressing and stamping, grease, oils, soap solutions and slushing compounds applied to reduce friction are generallv deficient in film strength and fail to provide optimum protection to the forming dies, while metallic coatings, such as lead and zinc, which provide more satisfactory die protection can only be removed with difliculty. The present invention provides a hard, dry, lubricating film, the 45- thickness of which can be varied to meet the requirements of the specific reworking process. The residue of this film remaining after working may be readily removed by immersion, in hot water.

In carrying outthis invention the wire or rods are first cleaned to remove scale and foreign mat ter, are sulled if desired, coated with line, and/ or tri-sodium phosphate and/or sodium carbonate and/0r sodium meta or ortho silicate, or proprietary mixtures of which the foregoing are ingredients, and baked or dried. Combinations of' these compounds may also be used. The question of whether the metal is sulled or limed de- .pends to a large extent on the type of work.

The coated wire "or rods are then drawn to 5 finish size, using as a lubricant the triglyceride of a fatty acid or a mixture of triglycerides of two or more fatty acids; these triglycerides conforming to the general type formula CnH2n-k08. The tri sodium phosphate or meta or ortho silil0 cates of soda serve as emulsifying agents to facilitate the subsequent removal in hot water of the lubricant. Although triglycerides conforming to the general type formula mentioned may all be usedto advantage, the most decided ad- 15 vantages are to be procured by the use of such compounds when n exceeds 38.

In the case of hot or cold rolled strip, the material is first cleaned of scale and foreign matter. It may or may not be'sulled or coated, or 20 both, as described in the case of wire or rods. It is then passed continually through either molten triglycerides of fatty acids, and wiped and cooled to solidification, or passed through a solution of triglycerides of fatty acids dissolved in a vola- 25 tile solvent, in which case drying may be effected either naturally or by the application of suitably proportioned heat.

I claim:

1. As an article of manufacture, a wire, rod, 0

or hot or cold rolled metallic strip having a lubricating coating of a compound having the general formula cnHznkos, where k may be 4 or 4 plus successive increments of 6, said coating being practically free from substances preventing 35 it from drying and hardening at atmospheric temperatures.- I

2. As an article of manufacture, a wire, rod, or hot or cold rolled metallic strip having a lubricating coating of a mixture of compounds all 40 having the general formula cnH2n-ko6 where'k may be 4 or 4 plus successive increments of 6, said coating being practically free from substances preventing it from drying and hardening at atmospheric temperatures.

' 3. In the manufacture of wire and rods, th steps consisting of cleaning to remove foreign matter, coating with-any one or combination of any two or more of the following, sull, lime, tri sodium phosphate, sodium carbonate, or sodium meta or. ortho silicate, and drawing through a suitable die with a lubricant whose ingredients conform to the general formula CnHin-kOG. where k is 4 or 4 plus increments of 6, said lubricant being practically free from substances prevent temperatures.

4. As an article of manufacture, a wire, rod, or hot and cold rolled strip, carrying a lubricant conforming to the general formula cumin-k0 and including tri sodium phosphate or meta or ortho silicates of sodium which serve as emulsifying agents to facilitate the subsequent removal in water of said lubricant.

5. In the manufacture of hot. or coldroll'ed strip, the steps consisting of cleaning to remove scale and foreign matter, and applying a lubricant whose ingredients conform toythe general formula Carlin-r06 where k is 4 or 4 plus increments of 6, by passing the strip continuously through said lubricant while the latter is molten and cooling to solidification, said lubricant being practically free from substances preventing it from drying and hardening at'atmospheric temperatures.

6. In the manufacture of hot or cold rolled strip, the steps consisting of cleaning the strip to remove scale and foreign matter, coating with sull, lime, tri sodium phosphate, sodium carbonate, sodium meta or ortho silicate, and applying a lubricant whose ingredients conform to the general formula CnHZn-kOG where k is 4 or 4 plus increments of 6, by passing the strip continuously through the said lubricant while the latter is v ing it from drying and hardening at atmospheric 7 at atmospheric temperatures.

molten and cooling to solidification, said lubricant being practically free from substances preventing it from drying and hardening at atmospheric temperatures.

7. In the manufacture of hot or cold rolled strip, the steps consisting of cleaning the strip to remove scale and foreign matter and applying a lubricator whose ingredients conform to the general formula CnH2n-k06 .where k is 4, or 4 plus increments of 6, by passing the strip continuously through the lubricant dissolved in volatile solvent, and drying the lubricant so applied, said lubricant being practically free'from substances preventing it from drying and hardening at atmospheric temperatures.-

8. In the manufacture of hot or cold rolled strip, the steps consisting of cleaning the strip to remove scale and foreign matter, coating with sull, lime, tri sodium phosphate, sodium carbonate, sodium meta or ortho silicate, and applying a lubricant whose ingredients conform tov the general formula Grimm-1:06 where k is 4 or 4 plus increments of 6, by passing the strip continuously through the lubricant dissolved in volatile solvent and drying the lubricant so applied,

said lubricant being practically free from substances preventing it from drying and hardening Nnisonw. DEMPSEY, 

